[Presenile dementia in memory clinics--incidence rates and clinical features].

This study describes the clinical features of presenile dementia diagnosed in memory clinics. It further gives an estimate of the declared incidence for the German city of Munich and surrounding counties. Twelve memory clinics in Switzerland and Germany were considered, among them all of the four in Munich. A total of 267 patients with onset of illness under the age of 65 were included. Only 16 patients (6%) were younger than 50. Men and women were affected about equally often. The most common cause of dementia was Alzheimer's disease (67%), followed by frontotemporal degeneration (13.5%) and vascular (5.6%) dementia. The declared incidence was estimated at 8.3 new cases of dementia per year among 100,000 persons in the 50-64 age range, with an incidence rate of Alzheimer's disease at 6.3/100,000. It can be concluded that memory clinics fulfill an important function in the care of patients with presenile dementia, since they are highly utilized by younger patients in early stages of the illness.